<template>
    <div class="app-container">
        <!-- 头部 -->
        <mt-header fixed title="GAG MSG">
            <span slot="left" @click="goBack" v-show="flag">
            <mt-button icon="back">返回</mt-button>
            </span>
        </mt-header>

        <!-- 组件切换 -->
        <transition>
        <router-view></router-view>
        </transition>

        <!-- 底部 -->
        <nav class="mui-bar mui-bar-tab">
        <router-link class="my-tab-item" to="/home">
        <span class="mui-icon mui-icon-home"></span>
        <span class="mui-tab-label">首页</span>
        </router-link>
        <router-link class="my-tab-item" to="/member">
        <span class="mui-icon mui-icon-contact"></span>
        <span class="mui-tab-label">会员</span>
        </router-link>
        <router-link class="my-tab-item" to="/shopcart">
        <span class="mui-icon mui-icon-extra mui-icon-extra-cart"><span class="mui-badge" id="badge">{{totalcount}}</span></span>
        <span class="mui-tab-label">购物车</span>
        </router-link>
        <router-link class="my-tab-item" to="/search">
        <span class="mui-icon mui-icon-search"></span>
        <span class="mui-tab-label">搜索</span>
        </router-link>
        </nav>

        
    </div>
</template>

<script>
import { mapGetters } from 'vuex'
export default {
    data(){
        return {
            flag: true,//默认显示返回按钮
        };
    },
    methods:{
        goBack(){
            //点击按钮向后跳转
            this.$router.go(-1);
        }
    },
    created(){
        if(this.$route.path==="/home"){
                this.flag = false;
            }else{
                this.flag = true;
            }
    },
    watch:{
        //当页面刷新的时候，不会触发watch中监听的路由地址变化
        '$route.path':function(newval,oldval){
            if(newval==="/home"){
                this.flag = false;
            }else{
                this.flag = true;
            }
        }
    },
    computed:{
        ...mapGetters(['totalcount'])
    }
}
</script>


<style lang="scss" scoped>

.v-enter{
    opacity: 0;
    //让即将进入的页面，向右偏移100%屏幕的宽度
    transform: translateX(100%);
}

.v-leave-to{
    opacity: 0;
    //让即将进入的页面，向右偏移100%屏幕的宽度
    transform: translateX(-100%);
    position: absolute;
}

.v-enter-active,
.v-leave-active{
    transition: all 0.4s ease;
}


.app-container{
    padding-top:40px;
    padding-bottom: 50px;
    //当有组件切换，一瞬间页面的宽度会变成正常宽的2倍，需要音程超出屏幕的宽度
    overflow: hidden;
}

.mint-header{
    z-index: 99;
}

.mui-bar-tab .my-tab-item {
    display: table-cell;
    overflow: hidden;
    width: 1%;
    height: 50px;
    text-align: center;
    vertical-align: middle;
    white-space: nowrap;
    text-overflow: ellipsis;
    color: #929292;
}

.mui-bar-tab .my-tab-item .mui-icon {
    top: 3px;
    width: 24px;
    height: 24px;
    padding-top: 0;
    padding-bottom: 0;
}

.mui-bar-tab .my-tab-item .mui-icon~.mui-tab-label {
    font-size: 11px;
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
}
</style>

